U.S. Pat. No. 5,494,609 discloses an electrically conductive coating composition comprising: a dispersion comprising dispersed particle of an intrinsically conductive polymer and, a solution which comprises a hydrophobic film-forming thermoplastic polymer, a highly polar plasticizer, and, an acid anhydride surfactant, in an organic solvent; wherein said thermoplastic polymer is soluble in said solvent to at least 1 percent by weight; and, wherein said dispersion comprises from about to 1 to about 50 percent by weight of said intrinsically conductive polymer.
EP-A 440 957 discloses dispersions of polythiophenes, constructed from structural units of formula (I): in which R1 and R2 independently of one another represent hydrogen or a C1-4-alkyl group or together form an optionally substituted C1-4-alkylene residue, in the presence of polyanions.
EP-A-686 662 discloses mixtures of A) neutral polythiophenes with the repeating structural unit of formula (I), in which R1 and R2 independently of one another represent hydrogen or a C1-4-alkyl group or together represent an optionally substituted C1-4-alkylene residue, preferably an optionally with alkyl group substituted methylene, an optionally with C1-12-alkyl or phenyl group substituted 1,2-ethylene residue or a 1,2-cyclohexene residue, and B) a di- or polyhydroxy- and/or carboxy groups or amide or lactam group containing organic compound; and conductive coatings therefrom which are tempered to increase their resistance preferably to <300 ohm/square.
EP-A 1 003 179 discloses a method for producing a polymeric conductive layer on an object comprising the steps of: providing an aqueous composition containing a polythiophene, a polyanion compound and an aprotic compound with a dielectric constant grater than 15.
WO 99/34371 discloses a silk screen paste with a viscosity of 1 to 200 dPa.s (102 to 2×104 mPa.s) containing a solution or dispersion of a conductive polymer paste and optionally binders, thickeners and fillers. WO 99/34371 also discloses a process for preparing silk screen pastes in which a solution or dispersion with a content of <2% by weight of poly(3,4-ethylenedioxythiophene) [PEDOT]/poly(styrene sulfonate) {PSS} is concentrated to a solids content of >2% by removing the solvent and subsequently optionally adding binder and/or filler. EXAMPLE 2 of WO 99/34371 discloses the use of the binder MIROX® TBN, a copolymer of sodium polyacrylate and NP 14-methacrylate from Stockhausen, in a PEDOT/PSS-containing silk screen paste.
EP-A 1 081 549 discloses a coating composition comprising a solution of a substituted or unsubstituted thiophene-containing electrically-conductive polymer, a film-forming binder, and an organic solvent media; the media having a water content of less than 37 weight percent. Coating dispersions with 0.1% by weight of PEDOT and with between 8 and 25% by weight of water were disclosed in the invention examples using a 1.22% by weight dispersion of PEDOT/PSS in water as the starting material.
EP-A 1 081 546 discloses a coating composition comprising a solution of an electrically-conductive polymer and an organic solvent media wherein the solvents are selected from the group consisting of alcohols, ketones, cycloalkanes, arenes, esters, glycol ethers and their mixtures; the media having a water content of less than 12 weight percent. Coating dispersions with PEDOT concentrations between 0.02 and 0.1% by weight and with between 2 and 8% by weight of water were disclosed in the invention examples using a 1.22% by weight dispersion of PEDOT/PSS in water as the starting material.
EP-A 1 081 548 discloses a coating composition comprising a substituted or unsubstituted thiophene-containing electrically-conductive polymer and an organic solvent media; the media having a water content of less than 12 weight percent. Coating dispersions with PEDOT concentrations between 0.02 and 0.1% by weight and with between 2 and 8% by weight of water were disclosed in the invention examples using a 1.22% by weight dispersion of PEDOT/PSS in water as the starting material.
There is a need for aqueous dispersions, printing inks and printing pastes for providing conductive layers with improved coating and/or printing properties.